<?php
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2014 - 2015, British Columbia Institute of Technology
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @package    CodeIgniter
 * @author    EllisLab Dev Team
 * @copyright    Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
 * @copyright    Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
 * @license    http://opensource.org/licenses/MIT    MIT License
 * @link    http://codeigniter.com
 * @since    Version 1.0.0
 * @filesource
 */
defined('BASEPATH') OR exit('No direct script access allowed');

/**
 * Config Class
 *
 * This class contains functions that enable config files to be managed
 *
 * @package        CodeIgniter
 * @subpackage    Libraries
 * @category    Libraries
 * @author        EllisLab Dev Team
 * @link        http://codeigniter.com/user_guide/libraries/config.html
 */
class CI_Config {

    /**
     * List of all loaded config values
     *
     * @var    array
     */
    public $config = array();

    /**
     * List of all loaded config files
     *
     * @var    array
     */
    public $is_loaded =    array();

    /**
     * List of paths to search when trying to load a config file.
     *
     * @used-by    CI_Loader
     * @var        array
     */
    public $_config_paths =    array(APPPATH);

    // --------------------------------------------------------------------

    /**
     * Class constructor
     *
     * Sets the $config data from the primary config.php file as a class variable.
     *
     * @return    void
     */
    public function __construct()
    {
        $this->config =& get_config();

        // Set the base_url automatically if none was provided
        if (empty($this->config['base_url']))
        {
            // The regular expression is only a basic validation for a valid "Host" header.
            // It's not exhaustive, only checks for valid characters.
            if (isset($_SERVER['HTTP_HOST']) && preg_match('/^((\[[0-9a-f:]+\])|(\d{1,3}(\.\d{1,3}){3})|[a-z0-9\-\.]+)(:\d+)?$/i', $_SERVER['HTTP_HOST']))
            {
                $base_url = (is_https() ? 'https' : 'http').'://'.$_SERVER['HTTP_HOST']
                    .substr($_SERVER['SCRIPT_NAME'], 0, strpos($_SERVER['SCRIPT_NAME'], basename($_SERVER['SCRIPT_FILENAME'])));
            }
            else
            {
                $base_url = 'http://localhost/';
            }

            $this->set_item('base_url', $base_url);
        }

        log_message('info', 'Config Class Initialized');
    }

    // --------------------------------------------------------------------

    /**
     * Load Config File
     *
     * @param    string    $file            Configuration file name
     * @param    bool    $use_sections        Whether configuration values should be loaded into their own section
     * @param    bool    $fail_gracefully    Whether to just return FALSE or display an error message
     * @return    bool    TRUE if the file was loaded correctly or FALSE on failure
     */
    public function load($file = '', $use_sections = FALSE, $fail_gracefully = FALSE)
    {
        $file = ($file === '') ? 'config' : str_replace('.php', '', $file);
        $loaded = FALSE;

        foreach ($this->_config_paths as $path)
        {
            foreach (array($file, ENVIRONMENT.DIRECTORY_SEPARATOR.$file) as $location)
            {
                $file_path = $path.'config/'.$location.'.php';
                if (in_array($file_path, $this->is_loaded, TRUE))
                {
                    return TRUE;
                }

                if ( ! file_exists($file_path))
                {
                    continue;
                }

                include($file_path);

                if ( ! isset($config) OR ! is_array($config))
                {
                    if ($fail_gracefully === TRUE)
                    {
                        return FALSE;
                    }

                    show_error('Your '.$file_path.' file does not appear to contain a valid configuration array.');
                }

                if ($use_sections === TRUE)
                {
                    $this->config[$file] = isset($this->config[$file])
                        ? array_merge($this->config[$file], $config)
                        : $config;
                }
                else
                {
                    $this->config = array_merge($this->config, $config);
                }

                $this->is_loaded[] = $file_path;
                $config = NULL;
                $loaded = TRUE;
                log_message('debug', 'Config file loaded: '.$file_path);
            }
        }

        if ($loaded === TRUE)
        {
            return TRUE;
        }
        elseif ($fail_gracefully === TRUE)
        {
            return FALSE;
        }

        show_error('The configuration file '.$file.'.php does not exist.');
    }

    // --------------------------------------------------------------------

    /**
     * Fetch a config file item
     *
     * @param    string    $item    Config item name
     * @param    string    $index    Index name
     * @return    string|null    The configuration item or NULL if the item doesn't exist
     */
    public function item($item, $index = '')
    {
        if ($index == '')
        {
            return isset($this->config[$item]) ? $this->config[$item] : NULL;
        }

        return isset($this->config[$index], $this->config[$index][$item]) ? $this->config[$index][$item] : NULL;
    }

    // --------------------------------------------------------------------

    /**
     * Fetch a config file item with slash appended (if not empty)
     *
     * @param    string        $item    Config item name
     * @return    string|null    The configuration item or NULL if the item doesn't exist
     */
    public function slash_item($item)
    {
        if ( ! isset($this->config[$item]))
        {
            return NULL;
        }
        elseif (trim($this->config[$item]) === '')
        {
            return '';
        }

        return rtrim($this->config[$item], '/').'/';
    }

    // --------------------------------------------------------------------

    /**
     * Site URL
     *
     * Returns base_url . index_page [. uri_string]
     *
     * @uses    CI_Config::_uri_string()
     *
     * @param    string|string[]    $uri    URI string or an array of segments
     * @param    string    $protocol
     * @return    string
     */
    public function site_url($uri = '', $protocol = NULL)
    {
        $base_url = $this->slash_item('base_url');

        if (isset($protocol))
        {
            $base_url = $protocol.substr($base_url, strpos($base_url, '://'));
        }

        if (empty($uri))
        {
            return $base_url.$this->item('index_page');
        }

        $uri = $this->_uri_string($uri);

        if ($this->item('enable_query_strings') === FALSE)
        {
            $suffix = isset($this->config['url_suffix']) ? $this->config['url_suffix'] : '';

            if ($suffix !== '')
            {
                if (($offset = strpos($uri, '?')) !== FALSE)
                {
                    $uri = substr($uri, 0, $offset).$suffix.substr($uri, $offset);
                }
                else
                {
                    $uri .= $suffix;
                }
            }

            return $base_url.$this->slash_item('index_page').$uri;
        }
        elseif (strpos($uri, '?') === FALSE)
        {
            $uri = '?'.$uri;
        }

        return $base_url.$this->item('index_page').$uri;
    }

    // -------------------------------------------------------------

    /**
     * Base URL
     *
     * Returns base_url [. uri_string]
     *
     * @uses    CI_Config::_uri_string()
     *
     * @param    string|string[]    $uri    URI string or an array of segments
     * @param    string    $protocol
     * @return    string
     */
    public function base_url($uri = '', $protocol = NULL)
    {
        $base_url = $this->slash_item('base_url');

        if (isset($protocol))
        {
            $base_url = $protocol.substr($base_url, strpos($base_url, '://'));
        }

        return $base_url.ltrim($this->_uri_string($uri), '/');
    }

    // -------------------------------------------------------------

    /**
     * Build URI string
     *
     * @used-by    CI_Config::site_url()
     * @used-by    CI_Config::base_url()
     *
     * @param    string|string[]    $uri    URI string or an array of segments
     * @return    string
     */
    protected function _uri_string($uri)
    {
        if ($this->item('enable_query_strings') === FALSE)
        {
            if (is_array($uri))
            {
                $uri = implode('/', $uri);
            }
            return trim($uri, '/');
        }
        elseif (is_array($uri))
        {
            return http_build_query($uri);
        }

        return $uri;
    }

    // --------------------------------------------------------------------

    /**
     * System URL
     *
     * @deprecated    3.0.0    Encourages insecure practices
     * @return    string
     */
    public function system_url()
    {
        $x = explode('/', preg_replace('|/*(.+?)/*$|', '\\1', BASEPATH));
        return $this->slash_item('base_url').end($x).'/';
    }

    // --------------------------------------------------------------------

    /**
     * Set a config file item
     *
     * @param    string    $item    Config item key
     * @param    string    $value    Config item value
     * @return    void
     */
    public function set_item($item, $value)
    {
        $this->config[$item] = $value;
    }

}
